Microsquirt E85 tuning question
I was looking at the Required Fuel settings because as I understand it this is the major constant change for gasoline to E85 settings. Mine has a value of 14.7 which to me would indicate a gas tune not an E85 tune. I would think it would need a value of about 9.5 +- for E85 . The car starts and drives part throttle acceptable for an initial tune with slight lean surge issues . I have a displayed wideband value of 14's at idle and low 13's under part throttle acceleration .
I am just wanting to make sure stuff is ok before I start trying to make power.
Here is a thread talking about the required fuel table.
http://www.msextra.com/forums/viewto...le+e85#p388791
Here is a pic of my settings

I to thought the same thing when I looked over the e85 tune. I messaged Denmah/Matt and he told me that its on a gas scale..... Load the tune, start it up and start tuning...
Microsquirt has a Flex fuel sensor input wire specifically for E85 tuning. Go to the junk yard and get an E85 sensor then install it per the MegaManual. Tune the Micro for pump gas using the AutoTune feature in TunerStudio. Then populate the E85 settings so it gives you the required Lambda.
That way no matter what you put in the tank it will constantly adjust fuel and timing based upon the existing measured alcohol %. Thats what the sensor is designed for and how it works in a factory config as well as in Misrosquirt software.
Done.
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If the VE table 1 is all that is modified thats just fine as i would just modify that. If there is another table that was modified for E85 it would help to know that.
Also e85 is never truly e85. The alcohol percentage varies greatly from tank to tank. Especially if you mix it with pump gas. That's why you tune it for pump gas and let the sensor modify the AFR and timing based on what ever is measured by the sensor in real time (what is going through the sensor now), not what was in the tank when you tuned it.
Get the ford sensor as the fuel fittings can be unscrewed and AN fittings can be screwed into it. The GM has pressed in quick disconnect fittings. Also if you are using a return fuel line, it can be pleased anywhere in the fuel stream. Pressurized or return line.
I data log my 2002 flex suburban with hp tuners and the alcohol content of pump 87 octane is generally 13-18 percent alcohol here in Kansas.
thanxs for your help
Mike
http://www.msextra.com/doc/ms3/flexfuel.html
http://www.msextra.com/forums/viewto...?f=131&t=40871
http://www.megamanual.com/mt29.htm#sf
I am still questioning the thought process ( not criticizing ) of the required fuel value being numbers that resemble gasoline and afr table that resembles gas as well.
somewhere when running different fuels with different fuel air ratio needs information would have to be changed other wise with no flex fuel type input device i could just pour in gas this tank and e85 the next tank and life would be fine.
so where is the information table at ( i am assuming VE table that is why i asked)
I have examined different strategies for tuning and it would make more sense to me if the gentleman that did the base tune was changing VE values that i would continue to change VE values instead of adding a new variable in altering required fuel as some do or AFR targets as some others do.
Maybe i am just not asking the question correctly, what makes this particular tune an e-85 tune and not a gasoline tune?
somewhere when running different fuels with different fuel air ratio needs information would have to be changed other wise with no flex fuel type input device i could just pour in gas this tank and e85 the next tank and life would be fine.
so where is the information table at ( i am assuming VE table that is why i asked)
I have examined different strategies for tuning and it would make more sense to me if the gentleman that did the base tune was changing VE values that i would continue to change VE values instead of adding a new variable in altering required fuel as some do or AFR targets as some others do.
Maybe i am just not asking the question correctly, what makes this particular tune an e-85 tune and not a gasoline tune?
Search for gas/e85 conversion table and it will make more sense....
My setup is almost like yours- microsquirt, 5.3, on3 76mm, 80injectors, ls6 cam, e85, but Im on a 58x motor. Depending on how soon you will start tuning, Im dyno tuning mine in 2 weeks and can send you my tune when its done if you need it...
If you tune it with E85, how will the Micro know when you are not running e85 (pump gas or mix) and make the changes necessary for Lambda?
E85 true alcohol % varies greatly and thus the true AFR will vary. Do you plan to run E85 from here to eternity at every fill up even when out of town?
So as I stated above, why not tune it for pump gas and let the E85 sensor make the real time, on the fly adjustments as designed since Micro has that capability already built into it?
All I am hearing is put E85 in the tank and tune it for that. Not why it is better in your opinion to do it that way.
last night my son and i took the twin turbo firebird and his turbo malibu to a cruise spot and had plans to go to the track for his first passes down a dragstrip but there was an event at the track and we both had put in a long day so we drove back home. hopefully next week we will have a chance again.
tonypaul: I would like to see your tune when you get a chance.






